Fe3O4水基磁流体的制备及其分散性能研究

采用共沉淀法制备了纯Fe3O4纳米粒子,分别用高氯酸、四甲基羟胺和油酸/十二烷基苯磺酸钠为表面活性剂对其进行表面处理后分散在水中,得到了3种水基磁流体,对这3种磁流体的浓度及稳定性进行了测定。实验结果显示:酸性、碱性和中性水基磁流体中Fe3O4的浓度分别为4.8%、5.8%和8.1%,其中中性水基磁流体中粒子的分散性能最佳;经过离心后,3种水基磁流体中的粒子均产生了沉降,且酸性和碱性磁流体中的粒子比中性磁流体中的粒子沉降的多。在此基础上,对影响粒子分散稳定性的机理进行了初步探讨。

Study on the preparation and stability of water - based magnetic fluids

Magnetite particles which were prepared by co-precipitation were treated by perchloric acid,tetramethylammonium hydroxide and oleic acid/sodium dodecyl benzene sulfonate and then dispersed into water respectively,then three kinds of water-based magnetic fluids were prepared.Their concentration and stability were determined.The experiment results demonstrated that the concentrations of magnetite particles dispersed in water were 4.8%,5.8% and 8.1% respectively.Among them,the dispersing stability of magnetite particles coated with oleic acis /SDBS were better than that of particles coated with perchloric acid and tetramethylammonium hydroxide.After centrifugation,the particles in the three kinds of water-based magnetic fluids sedimentated and the magnetite particles coated with oleic acis /SDBS was more stable than that of particles coated with perchloric acid or tetramethylammonium hydroxide.Based on those results,a primary study was performed on the mechanism of magnetite particles sispersed in water.